diff --git a/Authors b/Authors
index bd050059b5f9..fed10d0209e1 100644
--- a/Authors
+++ b/Authors
@@ -65,6 +65,7 @@ Josh Durgin <joshd@hq.newdream.net>
 Josh Kearney <josh@jk0.org>
 Josh Kleinpeter <josh@kleinpeter.org>
 Joshua McKenty <jmckenty@gmail.com>
+Julien Danjou <julien.danjou@enovance.com>
 Justin Santa Barbara <justin@fathomdb.com>
 Justin Shepherd <jshepher@rackspace.com>
 Kei Masumoto <masumotok@nttdata.co.jp>
diff --git a/nova/exception.py b/nova/exception.py
index 84c08dce80d9..56768b5896e0 100644
--- a/nova/exception.py
+++ b/nova/exception.py
@@ -735,7 +735,7 @@ class NetworkAdapterNotFound(NotFound):
 
 
 class ClassNotFound(NotFound):
-    message = _("Class %(class_name)s could not be found")
+    message = _("Class %(class_name)s could not be found: %(exception)s")
 
 
 class NotAllowed(NovaException):
diff --git a/nova/utils.py b/nova/utils.py
index c1862f316c73..1d2063798116 100644
--- a/nova/utils.py
+++ b/nova/utils.py
@@ -63,7 +63,7 @@ def import_class(import_str):
         return getattr(sys.modules[mod_str], class_str)
     except (ImportError, ValueError, AttributeError), exc:
         LOG.debug(_('Inner Exception: %s'), exc)
-        raise exception.ClassNotFound(class_name=class_str)
+        raise exception.ClassNotFound(class_name=class_str, exception=exc)
 
 
 def import_object(import_str):